Aircraft infrared (IR) signature studies are complex, due to their dependence on several parameters, e.g., line of sight ($\mathrm{LOS}$) and viewing aspect ($\widehat{\mathrm{LOS}}$). There is no equivalent counterpart of the well-known radar cross section (RCS) that can be easily used for obtaining IR lock-on range, $R_{\mathrm{LO},\lambda 1-\lambda 2}$. This study introduces the concept of IR cross section $(\mathrm{IRCS}{)}_{\lambda 1-\lambda 2}$ of complete aircraft as seen by seeker in ${\lambda }_1–{\lambda }_2$ band in $\widehat{\mathrm{LOS}}$ and of aircraft part in an orthogonal view. The IR solid angle (${\omega }_{\mathrm{IR},\lambda 1-\lambda 2}$) subtended by $(\mathrm{IRCS}{)}_{\lambda 1-\lambda 2}$ of complete aircraft and of an aircraft part is also introduced, which is the basis for redefined general criterion for lock-on by IR-guided missile. Equality based on ${\omega }_{\mathrm{IR},\lambda 1-\lambda 2}$ at aircraft part level and at complete aircraft level is the basis for obtaining $R_{\mathrm{LO},\lambda 1-\lambda 2}$ of complete aircraft in terms of its $(\mathrm{IRCS}{)}_{\lambda 1-\lambda 2}$. Dimensionless scalar factor, ${\mathrm{\Pi }}_{\mathrm{IRCS},\lambda 1-\lambda 2}$, converting visual area to $(\mathrm{IRCS}{)}_{\lambda 1-\lambda 2}$ is studied, for temperatures ranging from close to ambient to maximum afterburning (reheat) mode of aeroengine. The ${\mathrm{\Pi }}_{\mathrm{IRCS},\lambda 1-\lambda 2}$ enables assessment of effectiveness of IR seekers with single or dual bands, for all-aspect engagement and for rear-view only.

飞机红外 (IR) 特征研究很复杂，因为它们依赖于几个参数，例如视线（$\mathrm{服务水平}$) 和观看方面 ($\widehat{\mathrm{服务水平}}$）。众所周知的雷达截面 (RCS) 没有可轻松用于获得 IR 锁定范围的等效对应物，${\mathrm{电阻}}_{\mathrm{LO},\lambda 1-\lambda 2}$. 本研究介绍了红外截面的概念$(\mathrm{IRCS}{)}_{\lambda 1-\lambda 2}$ 导引头看到的完整飞机 ${\lambda }_1——{\lambda }_2$ 带入 $\widehat{\mathrm{服务水平}}$和飞机部件的正交视图。红外立体角（${\omega }_{\mathrm{红外线},\lambda 1-\lambda 2}$) 由 $(\mathrm{IRCS}{)}_{\lambda 1-\lambda 2}$还介绍了完整飞机和飞机部件的数量，这是重新定义红外制导导弹锁定通用标准的基础。平等基于${\omega }_{\mathrm{红外线},\lambda 1-\lambda 2}$ 在飞机部件级别和完整的飞机级别是获得 ${\mathrm{电阻}}_{\mathrm{LO},\lambda 1-\lambda 2}$ 就其完整的飞机而言 $(\mathrm{IRCS}{)}_{\lambda 1-\lambda 2}$. 无量纲标量因子，${\mathrm{\Pi }}_{\mathrm{IRCS},\lambda 1-\lambda 2}$, 将可视区域转换为 $(\mathrm{IRCS}{)}_{\lambda 1-\lambda 2}$研究了从接近环境温度到航空发动机最大加力（再加热）模式的温度。这${\mathrm{\Pi }}_{\mathrm{IRCS},\lambda 1-\lambda 2}$ 能够评估单波段或双波段红外导引头的有效性，用于全方位参与和仅用于后视。